Pure silicon is not a very good conductor of electricity. Its electrons are locked tightly in chemical bonds with neighboring silicon atoms. Scientists improve this by adding tiny amounts of different elements.
This adding process is called doping. To make a p-type semiconductor, they use elements like boron or aluminum. These specific elements have one less outer electron than silicon.
When a boron atom takes a spot in the silicon crystal, a gap appears in the bonding structure. This missing electron gap is known as a hole. The hole is not a physical object.
It is just an empty space where an electron should be. However, it behaves exactly like a particle with a positive charge. A nearby electron can easily jump into this empty hole.
When the electron moves into the hole, it leaves behind a brand new hole in its old spot. As electrons shuffle one way to fill the gaps, the holes appear to travel in the opposite direction. This movement of positive holes creates an electrical current.
The ‘p’ in p-type stands for this positive charge movement. These materials are totally useless on their own. They become powerful when joined with n-type semiconductors.
The n-type versions use extra electrons instead of holes. Together, they form the crucial building blocks of all modern computer chips and solar panels.